Instead of flooded with acid, the acid is absorbed in to glass mat that touches the lead. I think all AGM are SLA, Seal Lead Acid. With that, it means you can install the battery upside-down if you want and on the extreme end, it can probably take a literal bullet and still work, they are durable.I am still struggling to understand what different battery types mean for our cars. What's in the link (
Absorbent Glass Mat (AGM) Battery Information - Battery University ) helps a little, but I am still not completely clear.
In the old days, I could tell when I needed a new battery. The lights and accessories would dim/slow down more than I was accustomed to, when the engine was at idle or off. Signified the battery was not delivering as much current for a given voltage that it had in the past. Not sure how to tell now, with all these smart algorithms modifying the experience. How to tell, now? Is the first definite symptom a no-start? Or (hopefully), is the car's computer smart enough to tell me it's time for a new battery?
When I need a new battery, I would like to buy the brand and type that gives longest service life. Still hoping for an answer: What should I buy?
Oops, do the charging systems differ between Gen1 & Gen2, Diesel, and not? I have a Gen 2 gasoline.